Determination of the minimum effective productivity of borehole hydraulic monitoring equipment for the extraction of low-strength iron ores

Abstract

When developing technical specifications for technological equipment designed for borehole hydraulic monitoring extraction of high-grade, low-strength iron ores in mines, it is essential to understand the equipment parameters that must be maintained during operation. Using borehole hydraulic fragmentation compared to explosive methods will reduce harmful atmospheric emissions within mines, allow for the reuse of mine water for ore fragmentation, and, under certain conditions, could be more effective than explosive techniques. Based on an energetic cost comparison of explosive and hydraulic fragmentation methods, the study identifies productivity thresholds above which hydraulic monitoring fragmentation is preferable. The patterns have been established under conditions of large-scale ore blasting, where the consumption of explosives is minimized. These patterns relate to the specific consumption rates of four different types of explosives used in iron ore mines. The cost of explosives has a linear impact on the efficiency of hydraulic monitor ore breakage. Even at equal specific consumption levels of different explosive types, the difference in hydraulic monitor productivity can reach up to a factor of two. When the specific consumption of a single explosive type increases from 0,2 kg/ton to 0,6 kg/ton, the productivity of hydraulic monitor breakage decreases by a factor of 2,8. The minimum effective hydraulic monitor productivity of 3 tons per hour is achieved at a specific consumption of Aquanite of 0,6 kg/ton. Mine drainage pumps CNS-38-220 and CNS-60-330 are proposed as energy equipment, and their effective operational productivity limits for ore fragmentation have been established. For martite ores with a strength coefficient between 1 and 2, the required productivity levels for hydraulic fragmentation are 10 tons per hour when using pump CNS-38-220, and 20 tons per hour when using pump CNS-60-330. The introduction of downhole hydraulic monitoring fracturing in deep iron ore mines in Ukraine will allow the use of natural water inflow from the ore massif as a technological tool for performing one of the main processes of underground mining operations - breaking.Keywords: borehole hydraulic monitor, ore fragmentation, parameters, productivity, iron ore, explosives.